An unique association of Pinus palustris (longleaf pine) trees with Tradescantia hirsutiflora (spiderwort) growing in sandy soil in East Texas was documented. Ectomycorrhizal pine roots grew towards roots of spiderwort in natural soils, intertwined among and grew around the spiderwort roots. Longleaf pine roots penetrated the thick mucilaginous layer of exudates surrounding spiderwort roots, grew among the abundant root hairs, and became closely appressed to the spiderwort root surface. Injection of 14C(U)-sucrose into spiderwort stems resulted in the appearance of radioactivity in pine roots; likewise, its injection into pine roots resulted in the appearance of radioactivity in spiderwort roots. These results establish the fact that nutrient exchange can occur between trees and herbaceous monocotyledonous plants in a natural forest ecosystem. Evidence presented suggests the ectomycorrhizal fungus is involved in the transfer of nutrients between pine and spiderwort. Forest Sci. 30:892-896.